North Korea An 'Extraordinary Threat': US

North Korea remains an acute threat to the Indo-Pacific region, a senior Pentagon official said Thursday after Pyongyang blew up its liaison office with South Korea.

"As we've been starkly reminded in recent days, North Korea continues to present an extraordinary threat to the region and which demands our continued vigilance," said David Helvey, the acting assistant secretary of defense for Indo-Pacific security affairs.

"It's hard to tell what's going to unfold over the next few days and weeks. But I do think that it's important to say that we remain vigilant against any types of threats and provocations," said Helvey.

The demolition Tuesday of the liaison office in the Kaesong Industrial Zone -- just across the border in Northern territory -- came after Pyongyang vehemently condemned Seoul for anti-Pyongyang leaflets sent by defectors into the North and raised tensions on the Peninsula.

The destruction of the office made good on a threat by Kim Yo Jong, the powerful sister of North Korean leader Kim Jong Un. She had threatened last week to reduce to ruins an institution she called useless.

Helvey was cautious when asked about calls for strengthening the US military presence in South Korea and resuming military exercises that had been suspended to encourage US talks with the North on its nuclear program. The discussions have gone nowhere.

"I don't want to get ahead of any decisions that would be made," he said.

"But this is one of the things that we are constantly talking to our South Korean allies about," he said.

"And quite frankly, it's something that helps to preserve our interests and preserve peace and stability across the Indo-Pacific region," said Helvey.